M_(αβ) X-ray production cross sections of Pb and B iby 9–40 keV electron impact

The experimental data of Mαβ X-ray production cross sections for Pb and Bi by 9–40 keV electron impact have been given. Thin films with thick carbon substrates are used in the experiment. The effects of target structure on the Mαβ X-ray production cross sections are corrected by using the Monte Carlo method. The corrected experimental data are compared with calculated cross sections in terms of the distorted-wave Born approximation(DWBA) theory. The measured Mαβ X-ray production cross sections for Pb and Bi are lower than the DWBA calculations. The atomic relaxation parameters used in comparing the DWBA values with experimental results affect the degree of difference.     

Mαβ X-ray production cross sections of Pb and Bi by 9-40 keV electron impactMαβ X-ray production cross sections of Pb and Bi by 9-40 keV electron impact

The experimental data of Ma/3 X-ray production cross sections for Pb and Bi by 9-40 keV electron impact have been given. Thin films with thick carbon substrates are used in the experiment. The effects of target structure on the Ma/3 X-ray production cross sections are corrected by using the Monte Carlo method. The corrected experimental data are compared with calculated cross sections in terms of the distorted-wave Born approximation （DWBA） theory. The measured Ma/3 X-ray production cross sections for Pb and Bi are lower than the DWBA calculations. The atomic relaxation parameters used in comparing the DWBA values with experimental results affect the degree of difference.     

Phase behaviors of binary mixtures composed of banana-shaped and calamitic mesogens

In this work, five mixtures with different concentrations of banana-shaped and calamitic compounds have been prepared and subsequently studied by polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction on non-oriented samples. The phase sequences and molecular parameters of the binary systems are presented.     

Calibration of RPC-based muon detector at BESⅢ

The calibration algorithm for RPC-based muon detector at BESIII has been developed. The calibration method, calibration error and algorithm performance are studied. The primary results of efficiency and noise at layer, module and strip levels have been calibrated with cosmic ray data. The calibration constants are available for simulation and reconstruction tuning. The results of Monte Carlo and data are also compared to check the validation and reliability of the algorithm.     

Calibration of RPC-based muon detector at BESⅢ

The calibration algorithm for RPC-based muon detector at BESⅢ has been developed. The calibration method, calibration error and algorithm performance are studied. The primary results of efficiency and noise at layer, module and strip levels have been calibrated with cosmic ray data. The calibration constants are available for simulation and reconstruction tuning. The results of Monte Carlo and data are also compared to check the validation and reliability of the algorithm.     

Detection of the X-ray spectra of imploding neon Z-pinch with elliptically bent mica crystal spectrometer

A wide variety of X-ray and extreme ultraviolet diagnostics are being developed to study on Yang acceler- ator.An elliptically bent crystal spectrometer is designed with a focal length of 1350 mm.A mica crystal with an interplanar spacing of 1.984 nm bent onto an elliptical substrate with eccentricity of 0.9485 is used.The crystal analyzer covers the Bragg angle range from 30°to 60°.The mica crystal can efficiently reflect radiation in multiple orders,covering the entire spectral range from 0.1 to 1.73 nm except for a gap from 0.86 to 1.0 nm.The application experiment is performed on Yang accelerator using the bent mica crystal analyzer.Spectra of neon-puff Z-pinch plasmas are recorded with a X-ray film,showing the H-like and the He-like lines of neon.Each spectrum has been identified and used for the wavelength calibration, and most of the line radiation is contained in the He-αand the L-αlines.The experimental results have demonstrated that the spectral resolution approximates 379.     

Design and fabrication of broad angular range depth-graded C/W multilayer mirror for hard X-ray optics

Recently, with the development of hard X-ray telescopes[1-3] and the third generation synchrotron sources[4], hard X-ray focus optics have been applied widely. For such applications, the reflective mirrors with relatively broad angular range for hard X-ray radiation such as Cu Kα line (λ = 0.154 nm), are required to extend the view field and flux of optics, where bent crystal and single layer metal mirrors cannot be used be- cause of too small grazing incident angle. The periodic multilaye…     

Study on Synthesis and Gas Sensitivity of SnO2 Nanobelts

Tin dioxide （SnO2 ） nanobelts have been successfully synthesized in bulk quantity by the CVD process based on the thermal evaporation of tin powders. The x-ray diffraction analysis indicates that the nanobelts are the tetragonal futile structure of SnO2. Scanning electron microscopy and transmission electron microscopy observations reveal that the nanobelts are uniform. The selected-area electron diffraction analysis demonstrates that the nanobelts are single crystals. The energy dispersive x-ray analysis of the nanobelt shows that the nanobelts are composed of Sn and O, Gas-sensing components have been manufactured with prepared SnO2 nanobelts. Their performance indicates that SnO2 nanobelts have high sensitivity and selectivity to liquefied petroleum gas with fairly good response-recovery characteristic and stability at 220℃.     

α-decay half-lives of superheavy nuclei and general predictions

The generalized liquid drop model （GLDM） and the cluster model have been employed to calculate the α-decay half-lives of superheavy nuclei （SHN） using the experimental α-decay Q values. The results of the cluster model are slightly poorer than those from the GLDM if experimental Q values are used. The prediction powers of these two models with theoretical Q values from Audi et al. （QAudi） and Muntian et al. （QM） have been tested to find that the cluster model with QAudi and QM could provide reliable results for Z 〉 112 but the GLDM with QAudi for Z 112. The half-lives of some still unknown nuclei are predicted by these two models and these results may be useful for future experimental assignment and identification.     

Three-body Effect on Equation of State of Spin-polarized Nuclear Matter

The equation of state (EOS) of spin-polarized nuclear matter has been investigated within the spin-dependent; Brueckner-Hartree-Fock framework by adopting the realistic nucleon-nucleon interaction supplemented with a microscopic three-body force. The three-body force effects have been studied and stressed with a special attention. The calculated results are given in Fig.1. It is seen that; in the Brueckner-Hartree-Fock framework the predicted energy per particle of spin-polarized nuclear matter versus the neutron and proton spin-polarization parameters fulfills a quadratic law in the whole range of spin-polarization. The related physical quantities such as spin the Landau parameters Go in spin channel and G′0 in spin-isospin channel, have been also calculated.     

Research and Application of MEMS technique tat BSFF

LIGA technique has been developed since 1993 at BSRF,including the fabrication of LIGA mask, deep X-ray Lithography,electroplating,the pouring molding and the applications in some fields.The LIGA mask with gold absorbing structures of 20μm thick ness and 5μm width and Kapton membrane of around 5μm thicness has been successfull fabricated and applied to the deep X-ray lithography with the PMMA structure of 1mm thickness or obove.the beamline form a wiggler is used for the deep X-ray lithography of LIGA statiion and is open to othe institutes researching the deep X-ray lithography.The normal process of LIGA technique with the exception of molding has been established with the PMMA structures of 500μm thickness at BSRF.The largest aspect ratio of PMMA structrues can reach about 50 with the height of 500μm and the lateral siae of 10μm. The nickel and copper structures with the theickness of 0.5mm and 1mm have been made by using the electroplating technique.The SU8 as a resist material of deep etch lithography with UV light is also developed in the fabrication of LIGA mask and some devices at BSRF.Electromagnetic stepping micro motor,haet exchange,accelerator,structures used in the EDM(electro discharge machinging) are being developed for the future applications.     

MEASUREMENT OF L-SHELL IONIZATION CROSS SECTIONS FOR NIOBIUM BY ELECTRON IMPACT

L-shell ionization cross sections of Nb by electron impact in the energy range from 3 to 40 keV have been determined with a Si(Li) X-ray detector. Influence of reflected electrons from backing on the measurement was corrected using an electron transport model. The experimental results are compared with theoretical calculations of Gryzinski and McGuire.     

THE ELECTRON CYCLOTRON RESONANCE HEATING EXPERIMENTS ON HL-1 TOKAMAK

The electron cyclotron resonance heating (ECRH) experiments on HL-1 tokamak with 300kW of power generated by a gyrotron are described. With ECE diagnostics, a 30% increase of electron temperature has been obtained. The following phenomena have been observed with various diagnostics during ECRH: increase of radiation intensity of soft X-ray;amplitude change and period elongation of sawtooth oscillation; MHD instability suppression; increase of Hα spectral fine intensity and ionized impurity radiation from edge plasma;increase of the temperature and density of edge plasma. Although the total plasma energy content increases, the energy confinement time is decreased. Initial results of low voltage start-up experiments have also been obtained.     

Energy feedback and synchronous dynamics of Hindmarsh–Rose neuron model with memristor

We analyze the energy aspects of single and coupled Hindmarsh–Rose(HR) neuron models with a quadratic flux controlled memristor. The energy function for HR neuron with memristor has been derived and the dynamics have been analyzed in the presence of various external stimuli. We found that the bursting mode of the system changes with external forcing. The negative feedback in Hamilton energy function effectively stabilizes the chaotic trajectories and controls the phase space. The Lyapunov exponents have been plotted to verify the stabilization of trajectories. The energy aspects during the synchronous dynamics of electrically coupled neurons have been analyzed. As the coupling strength increases, the average energy fluctuates and stabilizes at the point of synchronization. When the neurons are coupled via chemical synapse,the average energy variations show three important regimes: a fluctuating regime corresponding to the desynchronized, a stable region indicating synchronized and a linearly increasing regime corresponding to the amplitude death states have been observed. The synchronization transitions are verified by plotting the transverse Lyapunov exponents. The proposed method has a large number of applications in controlling coupled chaotic systems and in analyzing the energy change during various metabolic processes.     

Nuclear Level Density with Non-zero Angular Momentum

The statistical properties of interacting fermions have been studied for various angular momentum with the inclusion of pairing interaction. The dependence of the critical temperature on angular momentum for several nuclei, have been studied. The yrast energy as a function of angular momentum for 28Si and 24 Mg nuclei have been calculated up to 60.0 MeV of excitation energy. The computed limiting angular momenta are compared with the experimental results for ^26Al produced by ^12C＋ 14N reaction. The relevant nuclear level densities for non-zero angular momentum have been computed for ^44Ti and ^136 Ba nuclei. The results are compared with their corresponding values obtained from the approximate formulas.     

Observation of Rotational Bands in Neutron—Rich ^106Mo Nucleus

The rotational bands up to a spin of 16h in the neutron-rich ^106Mo nucleus have been ivestigated by measuring high-fold prompt γ-ray coincidence events following spontaneous fission of ^252Cf with a Gammasphere detector array.The ground-state band,the one-phonon and two-phonon γ-vibrational bands,as well as a quasi-particle hand have been confirmed and expanded.The other four collective rotational bands,three proposed as two-quasi-particle bands and one proposed as a β-vibrational band,have been newly observed.The characteristics of these collective bands and the possible configurations for the quasi-particle bands are discussed.     

Solutions of the Schrdinger Equation with Quantum Mechanical Gravitational Potential Plus Harmonic Oscillator Potential

The solutions of the Schrdinger equation with quantum mechanical gravitational potential plus harmonic oscillator potential have been presented using the parametric Nikiforov–Uvarov method. The bound state energy eigen values and the corresponding un-normalized eigen functions are obtained in terms of Laguerre polynomials. Also a special case of the potential has been considered and its energy eigen values are obtained.     

Search for Double γ-Vibrational Bands in Neutron-Rich 105Mo Nucleus

Levels in the neutron-rich ^105Mo nucleus have been investigated by observing prompt γ-rays following the spontaneous fission fragments of^252 Cf with the Gammasphere detector array. The yrast band has been confirmed and updated. The other two collective bands with the band head levels at 870.5 and 1534.6 keV are newly observed, and they are suggested as the candidates for one-phonon K= 9/2 and two-phonon K = 13/2 double γ-vibrational bands, respectively. Systematic characteristics of these bands have been discussed.     

Structure and phase transition of a two-dimensional dusty plasma

The structure and phase transition of a two-dimensional (2D) dusty plasma have been investigated in detail by molecular dynamics simulation. Pair correlation function, static structure factor, mean square displacement, and bond angle correlation function have been calculated to characterize the structural properties. The variation of internal energy, shear modulus, particle trajectories and structural properties with temperature has been monitored to study the phase transition of the 2D dusty plasma system. The simulation results are in favour of a two-step continuous transition for this kind of plasma.     

Light—induced nonlinear effects of dispersion relation of ultracold Bose gas

We have investigated the optical properties of Λ-configuration ultracold dense Bose gas interacting with two laser pulses, which usually result in electromagnetically induced transparency. With the nonrelativistic quantum electrodynamics and taking into account the atomic dipole－dipole interaction and local field effect, we have derived the Maxwell－Bloch equations of the system. The dispersion relation of an ultracold Bose gas has been obtained and the light-induced nonlinear effects have been analysed. The light-induced nonlinear effects are different from the effects induced by two-body collision of Bose－Einstein condensation atoms which have a frequency shift of transparent window.